Automatic control equipment



I July 21, 1931. s Y 1,815,803

AUTOMATIC CONTROL EQUIPIENT Filed Aug. 19, 1929 Inventor- Har'old TSeeley,

His Attorney.

i "ifiiipiic tit'nffilea August 19, 1929 i swarm. 387,019.

' --M j1 anaa relates ammaeaneo1,

equipments andfparticularlyy-to automatic oontrolequipments for mercuryarc -recti fiersand its" object'isl'to provide an -arrange-;

5 ment of apparatus for 'efleeting the immedik are connection" of therectifier to a souree of e curr nt respon se to the establishment ofani'exciting are in 'the rectifier Whenthe recesnbsequent i reconnectionoff the rectifier to the supply'cirenit while theeqnipment is in voperationispnly iaft e'r the rectifier has been j ,dis'connectedfromjthesupply 'ciremt forfa relatively long} predetermined 7 length oftime. 1 Such an "arrangement is desirable in V order't'o makeuseof thequick starting 'aet'eristic-of a mercury arc rectifier. 1

-- 7 gMy invention will i be better understood jflfom thefollowingfdescription when taken in connection with "the" 'accompanyir1{drawings, which diagrammatically shows I an auto Inatic mercury arerectifier -contr'ol v equipment which embodies my invention, and its'Referringto" thefarrangement shown the' drawi ngsyl.represents amercur'y arc rectifier whi'chlis arranged tofbe intercon- -e nected.loetvs7 een an alternating current sup- .30 ply circuitQ and a'd'irectcurrent load circuit 3 byfm'eans ,offysuitable switchesgt and. '5'

I I respectively, fIniforder to obt'ainithedesired di ect currentvoltage from the rectifier l, a

, V I supply circuitQf The seeondary windings of the power,transformer'6are connected in star and the neutrals thereof are connected i'ng, istheground, i

i 'lhe rectifier- 1,comprises 'aipluralityof anodes 10,, which, areconnected to secondary P i terminals of the power-transformer 6, and acathode; 1 which is arran ed to be connected I to thepo'sitiveside ofthe direct current cirocuit' 3Yby the switch g I mean g CONTROLEQUIPMENT to be protided, In the present embodiment of my'invention Ihave shown the rectifier as I, 'being'provided withgan auxiliary'or arcstrikor; e i

p'e'fv'fill be pointed "out in the appended p I I H "ing anode 13Jforestablishing the arc; This powertransformer GiscOnneeted between the"matinee 1 and-the alternating current arc, current flows, after anarehas been es;

tablished 'in'the rectifier, from any anode 10 the current neverflowsinithe re erse direcconnected to the negative or groundedsi'de'pliasetransformer 7 and reactor, 8, eaeh an-* ode dnrin ga portion ofeach cycle of the al Y f l ternatingr icurrent hasfaipotential highervthan ny one of the other fanodesand during that period alloWsa currentto flow to the cathode" across the mercury are j after has once beenstarted;

- As the mercury ple s of which are well 1 knownfin the v art; has

a-node 13 isnormally held out of engagement with the. mercury'lby meansof aspring 14 and o 5 v is arranged to"be" moved into engagement withthe mercury by means of a 'solenoidj15 which when energized places thespring "145 under tension. Whenthe anode 13- engages the mercury acircuit from ,asuitablesonrce :ofcurrent, shown in the drawing as thegen eratorl 16016 21 motor generator set'17, is comsolenoid 15 so thatthe spring 14 draws the striking anode 13 out of the mercury and tifierfAfter the excitingarc has been ,estab current load circuit 3.

In accordance 1 4 a r i i far ;'1 :e "some form of arcestabl shingmeans, exam}.

' 30 fi YforflYfie r PEnNsYiLvANm,-Assm1qonmo ennnmnnnncmmc Y gCOMPA'NY,A CORPORATION on NEW YOR v t 1 pl e am g a co e ay 8 hw eh- V energized;effects the deenergization offthefi therebyestablishesan exeitin'garcintherec-L it ilished'the switches 4 and 5 are successively closed so thatcurrent flows from the-anodes '10 to'the cathode 11 of the rectifier:and in this I a manner energy istransferredfrom' thealter- H "nati ngcurrent supply Circuit 2 to the direct) thrthe mbodiment any Iinventionshown in the drawings,lthe normal starting and stopping of therectifier l'is ef j tested bythe Closing and opening eta/ h nd e coils'36" and frorn efl'ectingthe opening of the switchf4 until after thistransient has switch 14 is closed and which is arranged to 'for; apredetermined time after the switch 4" I disappeared.- In the particulararrangement shown in the drawing, this-result is obtained by providing arelay-4Q which is arranged to short-circuit the'coils 36 and 37 beforethe maintain the coils 36 and "37 short-circuited is closed. This resultisobtained' by connect.

, arewell knowniin the art'so that it does not in the drawingjisiiasfollows; "l/Vhen it is, de-,

7 f enits contacts until after the relay 'coilhas been deenergizedapre'determined length I oftiine.

' The operation, offthe arrangement shown sired to pla ceiihefrectifier]in operation, the control "switch 19 v is closedso that theimaster relay20Jand 'riorr'nally closed contacts 42 of thelockoutl relay 34,areconnected in series a acr "sjtliecontrol circuit 21;. The master re-'ny'euiby closing its contactsf4-3 connects the'rnotor '23 of'the'motorgeneratorset 17 V. acrossthe supply circuit 21 so that. the'motorgenerator setiishstarted to-effect theestahlish nent-fofan excitingarcin the, rectifier '1.

' As soonias the voltage ofithe'generator' lfi of mqtor gnemor c-se rtbuildsup to a predetermined value 'fthe solenoid '15" of the arc;establishing; means; I is; sufliciently' jener gizedto' move thestr ikina ode 13 intoen; 4

, gagernent withfthe' mercury of" the rectifier sojthattherel'ay opensits cone-Cesar a'ndf closesits contactsj45}; ';'I he[openingf of therelay contacts44, which are in the 'circuitof 1 the solenoid 1 5;efirejcts the' deene'rg 'ization ot a thej solerioid '15 so 'that the spi g 14 moves 7 the striking anode 113 outo'f engagenient with a the.rnerciiry and thereby establishes an exeg fIfheenergizifng circuitofethe solenoid '15 l also includes the contacts 44@ )f,the' controlrelay.;18.' As soon as the jstriking anode, 13

engagesfthe mercury in the rectifierggcurrent flows through the-[coil ofthe control relay. 18

citingf 'arc therectifier; Since the "are re-,

' sistance is low, suiiicient current; flows through-the are between thestriking anode 13 and i the mercurylto maintain the control relay118 inits energized position after the arcis establishedi In order .to limitthe current through the coilof the relay 18, it may be; desirablein'some casestoconnect a suitable resistor 46 inseries withcthe relaycoil;

r ie aila ngtup ofjthevoltag bfthe gen-,,

I v eratordB also effects the energization of the l y, hi habyf lQ i s't t ct 47 i J and 48, short circuits he overload'trip zcoils "36 37respectively so thatthe' inrush cu-re rent to the transformer 6, whenthe switch 4' When the switch 4 closes, its auxiliaryconftactselcomplete an energizingcircuit for-the closingcoil '52- of theswitch fi'acrossthe' direct current terminals of the rectifier 1 so thatthe-switch 5 is closed to connect the termined number of tim s, t

is subsequently closed, doesjnot efiectilth opening of the switch 4. H

relay 20, auxiliary contacts 49 of switch 4, coil of'relay 24, contacts45 of the relay 18,

time-delayed contacts 25 of the master re:

lay 20 to the otherside oithe'contr'ol circuit 21. .The-relay 24 byclosing its contacts 50 completes across the control circuit 21 an ensergizing circuit fr'dr the closing coi1-26 to efi'ect theclosing ofvtheswitch 4 so thatzthe re'ctifieri 1 is. connected to the supply,cirrectifier to the direct current load'circuitfi ifthe direct currentvoltage of ther e'ctifier is above-a predetermined value; The circuitgofthe closingvcoil52 also includes the contacts 53 of the master relay 20.r

a .When the switch 4 closes, its auxilia n tacts complete across thecontrol circuit 21 anenergizing circuit for theundenvoltag'e trip coil55 for the switch'4 so that the latch 56 is free to maintain the switch4" closed afterthe'closing coil 26 is deenergized 'by V the controlrelay 24 when its circuit is opened I by the auxiliary contacts 49 onthe switch 4.

The switch 4 by opening its auxiliary com 1 tact 41eiiects thedeenergization ofthe relay 19 Y 4 0; which after a predetermined -time,-intervalopensits contacts'47 and 48 and renders f u the overcurrenttrip coils 86 and 37operative p a toopen the switch 4. f Q

from the above description that if the exciting arc is established in VIt will be observed the 'rectifier 1 within a predetermined timeafterthe coil of the master relay 20 is enerter relay '20 in addition toinitiating the oper ation of the arc establishing means also com\-pletes an energ zing circuit for the release magnet 32 of the timingdevice 27 sojthat the operationof the timing device 27 is initiated-toclose the switch 4 in case it does not remain closed after theinitialreclosure Y thereof and to lock out the equipment if the ,1startingoperation is not completedwithin a predetermined time intervalafter thelmaster= we a relay '20 is energized or the switch4-fails toremain closed after being reclosed a predef n .The energizing circuit ofthe release-magnet 32 which is completedacross the 'control circuit 21by the closing of the contacts 43 s also includes the auxiliarycontacts49 on the switch 4'so that the release mag-net 32 is notenergized when the timer 28 is in its normal position andthe-switch 4isclos'ed. Therefore,.under normal operating conditions, the tuner 28remains in ltsnormal position.v

'11 'When the releasemagnet 321s energized, it withdraws the stop 30 outof engagement with the projection 31 so that-the motor- 29 can produceonefrevolution'of thetimer 28,

During this single revolution of the timer .28, it is arrangedtosuccessively close lts contacts 60 and-61 with-predeterminedtimeintervals between successiveclosures of the contacts. The'initialclosing of the contact 60,- h'owever, does nottake place until aftersufiicient time has elapsed to allow the me ter relay contacts to open'Therefore, under normal operating conditions the initial closing of thetimer conta'c-ts 'oO, when the rectifier is firststarted, :d'oes'not'occur until afterthe'swi'tch 4has been closedf Consequentlyflf theswitch 4 remains closed after the initial. closing thereof of successiveclosures ofthe timer contactsGO and '61 "do not v either an overload-oranyother abnormal condition while the rectifier isin operation,

theclosing of the. auxiliary contacts 49011 theswitch 4 eii'ect s, inthe manner above described, the energization or the release magnet 32*so that the operation of the timer 28 is efiected. After'a'predetermined time intervahthetimer 28 closes its contacts .60 andcompletes across" the control circuit 21 an energizmgcircuit for the,controlrelay 33 sincethe auxiliary contacts 49 of theiswitch 4'and thecontacts 43 of the master control relay 20 are closed. -The"contr,olrelay 33, when energized, completes a locking circuit for itself throughits contacts 62 so that the relay is not deene'rgiz ed' when the timer28 subsequently opens its contacts 60 and closes its contacts 61. The.subsequent closing of the. timer contacts '61 completes across thecontrol circuit 21, when the control relay 33 is energized, anenergizingcircuit for the control relay 24 whlch when energized ei-.fQCtS in the manner above described the closingof the switch 4 and'thesubsequent closing of the switch 5fwhich was openedin responselto' the,opening Lof the switch 4.

This energizing circuit for the control relayj 24 includes'the' contacts4301? the master control relay 20, the" auxiliary contacts 49- 64 whichare closed onthe switch4,coil of'the relay 24; contacts of the relay18', contacts 61 ofthe timer 28 and contacts 620i the control relay '33.

If the switch 4 remains closed after the firstreclosurethereofl'thetimer 28 returns to its normal position withouteffecting the operation of thecontrol relay '33 when it again closes itscontacts during its return movement. If, however, the switch 4 does notremain closed, the subsequent clos ing ofthetimer contacts 60 and 61eflectsin a manner above described another reclosure of the switch afterit has been openeda predet-ermined length of time. H- the switch 4 failsto remain closed after its second recl'osure, the timer 28 is arrangedto lock out the rectifier l. This resultis accomplished by providing thetimer '28 with the contacts justiprior to the timerreaching'itsnormalposition.

If the switch 5, is openso that its auxiliary contacts 65 are closedwhen the v timer 28 closes its contacts 64, a circuit, which alsoincludes the contacts 43 of the master relay 20 is completed across thecontrol circuit 21 for the-lockout relay '34." The lockout'relay 34' byopening its contacts '42 in the energizing circuit of the master relay20 effects the deenergization of the master relay and looks out theequipment'by preventing the master relay 20 from being energized inresponse "to the operation of the'control relay 20 until the lookoutrelay has I been reset latch 35 of the manually.

.- From theabove description 01E the (5 m:

tion it willbe seen that when the rectifier is' first placed inoperation, the switch 4 is closed immediatelyafter the exciting arc isestablished and without waitingfor the first closing operationof thetiming device 28"to occurl After he .rectifi been placed in operation,however, any'subsequentreclosure ofthe switch 4, such as occurs'afterthe switch has been opened in response to an overload; can takefplaceonly" after the timing device 28 has been .in operation for relativelylong predetermined length of time. 'By meansrof 'myinvention the timedelay of thetiming device 2:8 is eliminated during the startingoperationand, therefore, the time required to get the rectifier into theservice is greatly decreased.

Undernormal operation conditions: the rectifierl is shut down by theopening ofthe control switch 19 which .deenergizes the master relay 20;The master relay20 by opening its contacts 43'and 53 efi'ects thedeenergization of the low voltage trip coil 55 of the switch 4andth'eclosing coil 52 of the switch 5 so that the rectifier isdisconnected from the supply circuit'2 and theloadcircuit 3.- Theexciting arccis extinguished by-thesto'p pingof the motor generatorsetI17-which is effected by the opening of the contacts 43"of v '1 2.*Incombination, an electric circuit, a

the master relay the energizing of the motor'23. r

kWhile-I have, in accordance with the Patlent Statutes, Shown anddescribed my inven' 5 tion as applied to a particular systemv and asembodying various devices diagrammatical- 1y indicated, changesandfmodificationswill be obvious to those skilled in'the art and I,"

therefore, aim in the appended claims to cover all such changes and'modifications as invention; c

" What I claim as newjand desire to secure by Letters Patent ofthe'United States is:

1; combination, an electric circuit, a

mercury arc'rectifier, aswitch. for connecting said rectifiertosaidcircui-t, means for establishing an exciting arc; in saidrectifier, and means for efiec'ting the closingofsaidswitch immediatelyafter the exciting arc is .estab-J lished in saidrec'tifierand foreffecting any subsequent reclosure of said switch While said excitingarc is establishedonly after'a relatively long time intervalhas elapsedafter the opening of theswitchn I :mercury arc rectifier, a switchforconnect- 'ing' said rectifier to said circuit,meansfor es-'fitablishmg an exclting arc n sa1drect1fier,a 30

control devicefor eflt'ecting the operation of saidar'c establishingmeans, and means for effecting the closing'of said switch immediatelyafter the exciting arc is established whensaid are is established withina predetermined initial operation of the control device} a3.-lncombination, an electric circuit, a mercury arc rectifier,a'switch-for connectsaidrectifier to [said circuit, means forestablishingan exciting arcin said rectifier, av control deviceforeiiecting the operation ofsaidarc establishing means, means includ ing atimingdevice controlledby said switch and control device forefifectlngafter' a predetermined time interval the" closing of saidswitch when it isopen subsequently to the operation of said controldevice, and means responsive to the establishment of an arc in saidfrectifier' within 'ar'predeterminedtime after the operation of said.control "device vfor effecting independently of said timingdevic'e theimmediate closing of saidswitch. I

4.;In combination, an electrickfcircuit', a mercury arc rectifier, aswitch for connecting said rectifier to'said circuit, means forestablishing an'e 'xciting arc in said rectifier, a mafsc ter relay forcontrolling the, operation of said are establishing means, startingmeans for effecting; the operation of'said relay to means, a timingdevice controlled by said true spirit and scope of my establishing astarting arc in said]rectifier,- andmeans for cile'ctingthe immediateclos}, V I 1 ingof said switch in response to the'esta'bj-fl li'shmentofthe excitingarc in saidrectifiei nd'ror effecting only after arelatively long I opened by said overload responsive means; Incombination, ane electric circuit, a mercury arc rectifier, a switchbetween said-T rectifirj and fcircuitf overload responsive j of said arcestablishing means, and means for time after the operation of saidcontrol "de-j .ivice'andforefiecting after said predetermined't'imeandwhi'le said excitingarc is es- 1 tablished areclosu're of said switchonly at the end offla definite time interval after the 40f efiect theoperation of said arc establishing- 65' relayandfswitch'for eifectinafter jpre' v termined timeinte'rvals the c osing ofsai'd switchfaplur'alityfloftimes,*and'means cone; I trolled by'said mast'errelay for:efi'ectingthe j immediate closing of said switchfwhnian c Iarcisestablishedin 'said'rectifien withina Y v io iibf said relay iseltected'by said starting means combination, an electric'circni imercury arc rectifier, a switch betweenfisaid predeterminedtime theoperat rectifier and circuit; overload I responsive means'for opening sad sw tch, means for time'interval EL'I'BClOSHI'QQf said switch whenmeans for; opening said switch, meansfjfor' establishing a starting "arcin saidjrectifier, Y

a control deviceflfor effecting the operation effecting the immediateclosing of said switch when an arc is established in said rectifierWithin a predetermined time after the operation of said control deviceandJfor efi'ecting only after a relatively long time interval areclosure of'sa'id switch when opened by, T v said overload'responsivemeans subsequently to the initialclosing of said switch. I 7. Incombination, an electric circuit, mercury arc rectifier, a switchbetween said 7 I rectifier and circuit, overload responsivef means foropeningisaid switch,-means for establishing an arc insaid rectifier, amaster relay for controlling the operation of said arcestablishin'g'mcans, starting means io'r effecting the'operation of said relay toeffect the operation of said are establishing means, g I

means for effecting the immediateclosing of said switch when an arcis'established in said rectifier within a predetermined time I aftertheoperation of said master relay is} efiected by said starting means andtiming means controlled by said switch andrelay' i for efiecting onlyafter a relatively long time interval the closing of said switch whensaid switch is opened While said relay is operated. I to'eifect theoperationof the arc establishing HIQELDS.

means for opening said switch, means for establishing an arc in saidrectifier, a master i relay for controlling the operation of said arcestablishing means, starting means for effecting the'operation of saidrelay to effect the operation of said arc establishing means,

means controlled by said relay and arc estabe I lishing means foreffecting the immediate 1 1in-saidm fi r w hing Pl'f detQiEillg t m f -pati fi dm t W.

iseifecte'dby said starting'means and timing Closibg oi said swjtoliwhen an aro is-estab lfflliity of times f'with predetermniedtimeinte'rv'als betweenfreolosures when saiclswitch is opened by 7 saidoverload responsive means aftor said re'layhasbeen operated apredetermined le'ngth of time.

menouiy Zara i otifirji switoh for connecting said rectlfier to said,circu t, and automatlc control means for refiectlng H.145 Start ng andstopping Of said rectifier including means for stablishing n arcin.sai-d r ctifier', and means for efE-ecting theinitial Closing ofsaid;

switch immediately after the" exciting; arc .is

established during the starting operation and t I for efieotingonly'hfter prdeterminedtigne ssi f 6 V '7 mam-o8 means-controll d bysziid switch and relay for r I 'efiecting the Closing offs'aid switch aplu-

